Exclude ArrayBuffer creation from the reported time
Exclude ArrayBuffer creation from the reported time

R=tyoshino@chromium.org

Review URL: https://codereview.appspot.com/138060043
googlearchive/pywebsocket,googlearchive/pywebsocket,google/pywebsocket,googlearchive/pywebsocket,GoogleChromeLabs/pywebsocket3,google/pywebsocket,google/pywebsocket,GoogleChromeLabs/pywebsocket3,GoogleChromeLabs/pywebsocket3